1. Field of the Invention
The present invention relates to a composition for preparing an electron emission source, a method for preparing an electron emission source using the composition and an electron emission source, and more particularly, to a composition for preparing an electron emission source, the composition including a nano-sized inorganic material and a vehicle, a method for preparing an electron emission source using the composition, an electron emission source including a nano-sized inorganic material and a small amount of a residual carbon, and is further, an electron emission device including the electron emission source.
2. Description of the Related Art
Electron emission devices are devices that emit light by applying a voltage between an anode electrode and a cathode electrode to generate an electric field such that electrons emitted from an electron emission source on the cathode electrode collide with fluorescent materials in the anode side.
Carbon-based materials, including carbon nanotubes (CNTs) having a high electron conductivity, are excellent conductors and are used to focus an electric field. Further, carbon-based materials have a low driving voltage due to a low work function and an excellent electron emission. Therefore, carbon-based materials are used in electron emission sources for electron emission devices.
A method for preparing an electron emission source including CNTs includes, for example, a method of growing CNTs using chemical vapor deposition (CVD) or a paste method using a composition for preparing an electron emission source, which includes CNTs, etc. When the paste method is used, production costs may be reduced and an electron emission source can be formed in a larger area than when the CVD method is used. The composition for preparing an electron emission source that includes CNTs, is described, for example, in U.S. Pat. No. 6,436,221.
However, conventional electron emission sources that include carbon-based materials have insufficient properties, such as current density, lifetime, etc.